A team of European researchers has developed a theoretical model of cell division, a process by which a mother cell divides into two daughter cells. Division is an essential stage in the life of all cells as it participates in the body's growth and wound repair, combating infection and cell turnover. At any given moment in our bodies, some 250,000 million mother cells divide and form 500,000 million daughter cells. Each newly formed cell has a well determined location. The mother cell has a given place among other cells in a tissue and, to avoid disturbing this organisation, the daughter cells that it produces also have their own spots. The constraints imposed by the environment influence the division and position of the daughter cells, and this very precise positioning is indispensable in maintaining the shape of tissues and organs. In this latest piece of research, biologists from at France's Marie Curie Institute and physicists from Germany's Max Planck Institute used micro-technologies to study the effects of space and spatial limitations on the division and position of cells (orientation). From their observations, the researchers were able to come up with a theoretical model to predict the orientation of cellular division. The model, based on the forces acting on the mitotic spindle inside the cell, is able to determine whether the division of a cell will proceed correctly. In addition, the model is able to show that certain micro-environmental elements will result in the asymmetric division of cells - two non-identical cells formed by the division of a mother cell. So the model could be used by doctors to refine their diagnostics when dealing with deregulation in the division of a pathological cell that could give rise to cancer.